Light and electron microscopic studies of the trachea in the one-humped camel (Camelus dromedarius)

Histology of trachea of camel (Camelus dromedarius) was studied using light, scanning (SEM) and transmission electron microscopy (TEM). Tissue samples taken from the trachea (proximal, middle and distal part) were routinely prepared for histology (LM, EM) and stained with haematoxylin and eosin, Van Giesson (VG), Alcian blue, Periodic acid schiff (PAS), Masson's trichrome (MT), Verhof, PAS-VG and PAS-MT. The trachea of camel consists of 66-75 incomplete cartilaginous rings of hyaline. The lamina epithelium is composed of pseudostratified-ciliated columnar epithelium with many goblet cells. Submucosal layers were loose connective tissue with many elastic fibres. The mucosal and submucosal layers were 517.2 +/- 61.6 microm (n = 20) thick. Submucosal glands were tubuloalveolar with mucous (acidic and neutral) secretions. Trachealis muscle was attached to the inside sheet of tracheal cartilage. Ultrastructural studies showed that surface epithelium is pseudostratified with mucus-producing goblet cells, ciliated and basal cells, similar to other mammals. The ciliated cells contained many mitochondria, oval nucleus and many big granules. In scanning electron microscopy (SEM) studies, viscoelastic layers were observed on the epithelial surface of trachea, and there were highly condensed cilia under this layer.     

Ultrastructure of the thyroid gland of the one-humped camel (Camelus dromedarius)

Follicular epithelium of the thyroid gland of the one-humped camel was examined by light and electron microscopy. It consisted of a single type of epithelial cell which varied from flattened to columnar in shape. Follicular epithelial cells were characterized by the presence of markedly dilated cisternae of rough-surfaced endoplasmic reticulum, well developed Golgi apparatus, abundant small vesicles (150 nm to 200 nm in diameter) in the apical cytoplasm, and electron-dense colloid droplets measuring from 250 nm to 1600 nm. Follicular epithelial cells frequently showed apocrine secretion into colloidal lumens. Apocrine protrusions with smooth surface were dome-like or balloon-like structures and contained a fine granular matrix. These findings indicate that the morphological features of the follicular epithelial cells of the thyroid gland of the camel are essentially similar to those of mammals except for the presence of apocrine secretion, which is unique to the camel.     

Prenatal development of the adrenal gland in the one-humped camel (Camelus dromedarius)

With 14 figures and 3 tables SUMMARY: Each adrenal gland consisted of cortex and medulla that developed from different embryological origins and presented different cellular organization. One hundred male or female camel embryos or fetuses with crown vertebral rump lengths (CVRL) that ranged from 0.8 to 117 cm were examined. The adrenal cortex, which is derived from intermediate mesoderm, was first observed in the 0.8-cm CVRL camel embryo. The adrenal cortex initially was combined with the gonad as a thickened region of proliferating cells derived from splanchnic intermediate mesoderm. Adrenocortical tissue was first separated from the gonadal tissue in the 2-cm CVRL camel fetus and was observed as a separate dorso-medial mass of cells. At 2.5-cm CVRL, the adrenocortical tissue was surrounded by a capsule of undifferentiated mesenchymal cells, except at its proximal pole, where an invagination was located through which chromaffinoblast cells entered the cortex. The chromaffinoblast cells migrated from the neural crest to form the medulla of the developing adrenal gland. In the 3.5-cm CVRL camel fetus, the adrenocortical cells differentiated into two layers: the inner fetal cortex and the outer definitive cortex. As development proceeded, the fetal cortex degenerated and the definitive cortex formed the zona glomerulosa and zona fasciculata. The zona reticularis did not form until the end of gestation. During prenatal life, the adrenal medulla was much thicker than the cortex.     

Development of the mesonephros in camel (Camelus dromedarius)

The study of the development of the mesonephros in the camel (Camelus dromedarius) was carried out on 16 embryos ranging from 0.9 to 8.6 cm crown vertebral rump length (CVRL). At 0.9 cm CVRL, the mesonephros is represented by a narrow strip along the roof of the thoracolumbar part of the vertebral column. At 1.4 cm CVRL, some of the mesonephric tubules are canalized but others are still solid. The mesonephric corpuscles are well developed at 1.9 cm CVRL and occupy almost the entire abdominal cavity in between the liver and the gut. Histologically, the glomeruli occupy the ventromedial aspect of the mesonephros while the mesonephric tubules become numerous, larger and more coiled. At 3 cm CVRL, the metanephros is invaginated in the caudal pole of the mesonephros, and the mesonephric tubules in some areas are differentiated into secretory and collecting tubules. At 3.5 cm CVRL the mesonephros is related dorsally to the postcardinal vein and ventrally to the subcardinal vein. At 4.7 cm CVRL continuous regression of the mesonephros from cranialwards to caudalwards is observed. At 5.3-5.5 cm CVRL, the cranial part of the mesonephros is divided into medial and lateral regions, and later the medial region completely disappears and is replaced by the primordium of the adrenal gland. At 8.6 cm CVRL, the caudal part of the mesonephros completely disappears.     

Actinomycosis in a one-humped camel (Camelus dromedarius)

An actinomycotic granuloma caused by Actinomyces viscosus is reported in a dromedary camel. Two hard, cutaneous, large granulamatous nodules were present on both sides of the postero-ventral side of the mandible exhibiting exudation and necrosis. After radical excision of the lesion, the daily treatment with penicillin-streptomycin combination was continued for 4 weeks. About 8 and 24 weeks from the initial treatment, no new nodules were noticed.     

Coronary arterial anatomy of the one-humped camel (Camelus dromedarius)

The detailed coronary arterial anatomy of seven camels was studied and compared with that of horses and cattle. In camels, there is a bilateral coronary supply, the right coronary artery being the larger. The left coronary artery follows the same pattern as that in horses. The ramus collateralis proximalis in camels separates off some distance away from the origin of the ramus interventricularis paraconalis, as in horses, whereas it separates off very quickly in cattle. The ramus collateralis distalis has two branches in camels, whereas the left distal ventriculi ramus does not branch. The ramus angularis is also absent but the left distal atrii ramus is present.Abbreviations LCR left ramus circumflexus - RCR right circumflexus ramus - RIS ramus interventricularis subsinosus - RIVP ramus interventricularis paraconalis     

Seroprevalence of camel brucellosis (Camelus dromedarius) in Somaliland

The present study was delineated to investigate the prevalence and risk factors of camel brucellosis in Northern Somalia (Somaliland). The study was carried out at three main districts of camel-rearing regions of Somaliland (Awdal, Waqoyi Galbed and Togdheer) in the period from July to November, 2008. A total of 1246 camel blood sera were randomly collected from 42 sporadic small scale camel herds. Two serological tests were used to screen all serum samples, Rose Bengal Plate Test (RBPT) and indirect ELISA (I-ELISA). Multivariate logistic regression was constructed to study the risk factors associated with Brucella seropositive cases. The overall prevalence of camel brucellosis in districts under investigation was 3.9% by RBPT and 3.1% by (I-ELISA). Multivariate logistic regression on animal level showed that locality (P < 0.05; OR: 6.254; CI, 1.186–32.976), herd size (P < 0.001; OR: 5.493; CI, 2.956-10–207), rearing with other ruminants (P < 0.001; OR: 12.433; CI, 3.957–39.060), and contact with other camels (P < 0.05; OR: 5.311; CI, 1.093–25.800) were the potential risk factors. However, herd size (P < 0.05; OR: 5.425; CI, 1.181–24.932), and rearing with other ruminants (P < 0.05; OR: 20.466; CI, 1.456–28.638) were recorded as risk factors on the herd level. The results of the present investigation indicate that the Brucella spp. exists within the camel herds in Somaliland. Further studies need to be done on Brucella infection in the other ruminants to determine which measure should be followed for control of brucellosis.     

Grain founder in a male camel (Camelus dromedarius)

A rare case of laminitis was recorded in an adult camel that was kept in confinement without giving any exercise and fed daily with considerable quantity of pearl millet grains (Pennisetum typhoideus) for more than five months.     

A quantitative study of the circulus arteriosus cerebri of the camel (Camelus dromedarius)

The afferent vessels of the circulus arteriosus cerebri in the camel were studied quantitatively. It was found that the diameters of the arteries did not differ significantly on the left and right sides. An interesting observation was that the basilar artery contributed to the blood supply of the brain in the camel, in contrast to the situation in other ruminants.     

Morphogenesis of lingual papillae of one‐humped camel (Camelus dromedarius) during prenatal life: A light and scanning electron microscopic study

This study was made on 24 camel fetuses of crown‐rump vertebral length (CVRL) ranging from 10.5 cm to 105 cm CVRL (94–352 days old). These camel fetuses were classified into three groups representing the three trimesters of prenatal life. During the first trimester (94–142 days), lingual papillae (circumvallate and lentiform papillae) were demonstrated on the lingual root, but lingual body and the apex were almost free of papillae except for some scattered epithelial projections especially near the lateral borders of the body. In the second trimester (152–229 days), the lentiform papillae covered the entire root of the tongue except for areas occupied by the circumvallate papillae. Taste buds with clear pores were observed for the first time in areas between the circumvallate gustatory furrow and surface epithelium of the tongue. In addition, short numerous filiform papillae were observed on the rostral part of the lingual body and the lateral parts of the apex. Fungiform papillae, however, were demonstrated amidst the filiform papillae. In this trimester, taste buds were also seen on the top of the fungiform papillae. In the third trimester (256–352 days), all lingual papillae were clearly demonstrated on the dorsum of the root, body and apex of the tongue. Both types of gustatory papillae (circumvallate and fungiform) had well‐developed taste buds. Mechanical papillae (filiform and lentiform) were well developed. Lentiform papillae occupied most of the dorsal aspect of the Torus linguae; they were larger in size with semicircular apices. Filiform papillae, however, were numerous and demonstrated heavily on the lateral and rostral parts of the body as well as on the apex of the tongue.     

Studies on the digestion of carbohydrates in the camel (Camelus dromedarius)

Summary Camels with cannulas in the small intestine were used to study the digestive-absorptive capacities of the small intestine. Solutions of different carbohydrates were infused through the cannulas and the responses in blood glucose levels were measured.Monosaccharides were readily absorbed from the camel small intestine. The pattern of disaccharide absorption indicated that there was high lactase activity and low maltase and sucrase activity, in the camel small intestinal mucosa.

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Estudios Sobre La Digestión De Carbohidratos En Los Camellos (Camelus Dromediarius)

Resumen Se instalaron cánulas en el intestino delgado de camellos, para estudiar la capacidad digestiva-absortiva, Se utilizaron las cánulas para infundir a través de ellas una serie de soluciones diferentes de carbohidratos, midiendo de esta manera los niveles de glucosa sanguínea.Los monosacáridos se absorbieron fácilmente. El patrón absortivo de los disacáridos indicó que la actividad de la lactosa fue alta y baja la de la maltasa y sucrasa.

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Etudes Sur La Digestion Des Hydrates De Carbone Chez Le Chameau (Camelus Dromedarius)

Résumé Les capacités digestives et d'absorption du petit intestin du chameau ont été étudiées à l'aide de cannules placées à ce niveau. Des solutions de différents hydrates de carbone ont pu être ainsi introduites dans la lumière du petit intestin avec mesures des taux de glucose dans le sang.Les monosaccharides ont été rapidement absorbés par le petit intestin du chameau. Les essais portant sur l'absorption de disaccharides ont montré l'existence d'une importante activité des lactases et d'une activité basse en ce qui concerne le maltose et le sucrose, dans le mucus du petit intestin du chameau.

     

Pythiosis in a dromedary camel (Camelus dromedarius).

A 4.5-yr-old male dromedary camel (Camelus dromedarius) was evaluated for a mass on the right side of the face. A complete blood count and blood chemistry revealed anemia and hypoproteinemia. Radiographs did not reveal bony involvement. The mass was resected and Pythium insidiosum was cultured. The camel was treated with an experimental immunotherapeutic vaccine and with sodium iodide and ceftiofur. The camel began to lose weight postoperatively and died 6 mo later. At necropsy, the camel was found to have gastritis of the third compartment of the stomach with intralesional hyphae of this oomycete pathogen.